Amyloidosis occurs when normally soluble proteins misfold into sticky, beta-sheet-rich structures that aggregate into insoluble fibrils. These fibrils accumulate in tissues, disrupting organ function as they build up. The disease is broadly divided into systemic forms, where deposits spread throughout the body, and localized forms, where they remain confined to a single organ or tissue. Pulmonary involvement is well documented in immunoglobulin light-chain amyloidosis, the most common type affecting the lungs. But transthyretin-related amyloidosis, known as ATTR, is a different story entirely: it rarely touches the lungs at all, and when it does, its clinical features remain poorly characterized because so few cases have been described.

ATTR itself comes in two flavors. Hereditary ATTR results from pathogenic mutations in the TTR gene and runs in families. Wild-type ATTR, by contrast, is primarily an age-related phenomenon in which the normal transthyretin protein, a carrier molecule that transports thyroxine and retinol-binding protein in the blood, becomes progressively prone to misfolding over decades. In both forms, the heart, peripheral nervous system, and eyes are the organs most frequently affected. The patient in this report had no family history of amyloidosis, and genetic analysis of her peripheral blood found no pathogenic TTR variants, pointing firmly toward the wild-type, age-related variety.

When the woman was referred emergently to the hospital, her oxygen saturation had dropped and a chest radiograph revealed a new infiltrative opacity in the left mid-to-lower lung field, layered on top of a nodular opacity that had been monitored for roughly a decade. Chest computed tomography added crucial detail: bilateral bronchial wall thickening, material retained inside the left main bronchus suggestive of blood clots, infiltrative opacities concentrated in the left upper lobe, and a calcified nodule. Notably, her white blood cell count and C-reactive protein were not elevated, biochemical and coagulation parameters were normal, and tests for tuberculosis and tumor markers all came back negative, narrowing the differential diagnosis considerably.

After initial stabilization with hemostatic agents, the clinical team turned to bronchoscopy, the procedure that would ultimately crack the case. The scope revealed irregular, bumpy mucosal lesions with a whitish-to-erythematous appearance extending from the trachea into both bronchi, while the peripheral airways showed diffuse wall thickening with luminal narrowing. A biopsy taken from the right upper lobe bronchial orifice, along with a bronchial aspirate, provided the tissue needed for definitive analysis. Under the microscope, pathologists found amorphous, pale eosinophilic material in the subepithelial region and around vascular walls, the classic histological signature of amyloid deposition.

Confirming the specific protein type required a sequence of staining techniques. Congo red staining, the gold-standard screen for amyloid, was positive, and the deposits resisted potassium permanganate treatment, a step that helps distinguish certain amyloid subtypes. Immunohistochemistry then delivered the decisive result: the deposits stained positive for transthyretin, establishing a diagnosis of ATTR amyloidosis. Without this layered pathological workup, the deposits could easily have been misclassified as the far more common light-chain variety, which would have sent the diagnostic workup in an entirely different direction.

Excluding systemic disease was the next painstaking task. Electrocardiography, echocardiography, and myocardial scintigraphy showed no evidence of cardiac amyloidosis, the most common and dangerous manifestation of ATTR. The patient had no sensory, motor, or autonomic nervous system symptoms, and orthopedic evaluation ruled out carpal tunnel syndrome and spinal stenosis, both frequent early signs of systemic ATTR. Ophthalmologic examination was unremarkable. To exclude multiple myeloma and other plasma cell disorders, hematologists assessed serum and urine monoclonal proteins and serum free light chains and performed a bone marrow biopsy, all of which were normal. Gastrointestinal biopsies obtained by endoscopy showed no amyloid deposition either. Collectively, these findings established that the disease was truly localized to the tracheobronchial tree, a phenotype the authors describe as exceptionally rare.

The story took one more twist when cultures of the bronchial aspirate grew Aspergillus fumigatus and Mycobacterium mucogenicum, two opportunistic organisms colonizing the damaged airway. Because both amyloid deposition and airway infection could have contributed to the hemoptysis, the team prescribed oral itraconazole for approximately one year and managed the mycobacterial infection conservatively. A CT scan performed a year later showed reduced endobronchial secretions and improved pulmonary opacities, even though the bronchial wall thickening persisted. The patient has experienced no recurrent bleeding, no progression of the airway lesions, and no emergence of systemic disease during follow-up, an encouraging outcome for a condition with no standardized treatment.

The case also carries broader lessons about how unexplained hemoptysis should be investigated. Dyspnea is the most common presenting symptom of pulmonary amyloidosis, followed by cough, weight loss, and chest pain; hemoptysis accounts for only about seven percent of presentations. Tracheobronchial amyloidosis can cause secondary infections and bleeding through mucosal fragility and bronchial stenosis driven by submucosal amyloid deposits. A prospective study of 606 patients with hemoptysis found diagnostic yields of 77.3 percent with CT, 48.7 percent with bronchoscopy, and 83.9 percent with a combined approach. In many cases, CT alone can identify the culprit, for instance when it reveals cavitary opacities strongly suggestive of tuberculosis alongside positive sputum testing. But when imaging and noninvasive tests fail to explain the bleeding, or when airway lesions are suspected, bronchoscopy can supply information nothing else can. In this patient, bronchoscopic biopsy delivered the pathological diagnosis of ATTR amyloidosis, and bronchial aspirate culture uncovered the concurrent infection that may have aggravated the bleeding, directly shaping the treatment strategy.

Treatment options for localized tracheobronchial amyloidosis remain frustratingly limited. Disease-modifying therapies for ATTR, including transthyretin stabilizers and gene-silencing agents, are approved in Japan for cardiac or neurologic involvement, but their efficacy in pulmonary disease is unknown. For airway-limited disease, interventional approaches such as bronchoscopic debulking, laser therapy, and radiotherapy have been reported, yet no standardized treatment has been established, and the evidence base rests on scattered case reports rather than controlled trials. Patients with progressive airway stenosis or recurrent hemoptysis may require such interventions, though this patient has so far been spared. The authors argue that their report demonstrates that tracheobronchial-localized ATTR can occur, however rarely, and that amyloidosis deserves a place in the differential diagnosis of hemoptysis. As wild-type ATTR becomes increasingly recognized in aging populations worldwide, clinicians evaluating unexplained airway disease may need to keep this vanishingly rare entity in mind, because the cost of missing it is measured in delayed diagnoses and unexplained bleeding that could otherwise be explained.

Subject of Research: Localized wild-type transthyretin amyloidosis of the tracheobronchial tree diagnosed after hemoptysis

Article Title: Localized Tracheobronchial Transthyretin Amyloidosis Diagnosed After Hemoptysis: A Case Report

Article References: Inoue, K., Tanaka, Y., Yanagi, M., Michimata, H., Nagahisa, Y., & Kondoh, S. (2026). Localized Tracheobronchial Transthyretin Amyloidosis Diagnosed After Hemoptysis: A Case Report. Respirology Case Reports, 14(10), Article e70781. https://doi.org/10.1002/rcr2.70781

Image Credits: AI Generated

DOI: 10.1002/rcr2.70781

Keywords: amyloidosis, transthyretin, ATTR, tracheobronchial amyloidosis, hemoptysis, bronchoscopy, Congo red staining, wild-type ATTR, pulmonary amyloidosis, airway disease, case report, respirology

The new server builds on COCaDA, short for COntact search pruning by C-alpha Distance Analysis, a command-line tool the group previously developed for detecting interatomic contacts at large scale. The core insight behind COCaDA is elegantly simple: rather than exhaustively checking every possible pair of atoms in a protein — a computation that grows explosively with protein size — the algorithm uses the distances between C-alpha atoms, the backbone reference points of each amino acid residue, to prune the search space. If two residues’ C-alpha atoms are too far apart for any of their side-chain atoms to plausibly interact, the algorithm never bothers examining those atom pairs at all. This pruning strategy slashes the computational cost of contact detection dramatically, making it feasible to analyze entire structural databases rather than one protein at a time. COCaDA-web now wraps that engine in an interactive interface and adds a precomputed database of roughly 746 million contacts, divided into about 690 million contacts within single protein chains and 55 million contacts between different chains.

Speed is one of the platform’s headline claims. According to the authors, COCaDA-web takes less than a second to process proteins of up to 1,000 residues, a size range that covers the vast majority of entries in the Protein Data Bank. That kind of responsiveness transforms the workflow of exploratory analysis. Instead of submitting a job, walking away, and returning hours later to a static text file, researchers can adjust parameters, rerun the analysis, and watch the results update in real time. The results for each protein entry are presented in a dynamic table that can be filtered and interrogated, alongside an interactive three-dimensional visualization that lets users see exactly where the detected contacts sit in the folded structure. For those who prefer to work in professional molecular graphics software, the server also generates annotated PyMOL sessions, pre-packaged so that the contact analysis can be opened, inspected and repurposed directly in one of the field’s standard visualization environments.

Two features distinguish COCaDA-web from earlier contact-analysis efforts. The first is pH value customization for protonation-aware analysis. Protonation — whether a particular chemical group on an amino acid carries an extra proton or has lost one — changes with the acidity of the surrounding environment, and those changes alter which atoms can form hydrogen bonds and salt bridges. A histidine residue that is positively charged at pH 5 may be neutral at pH 7.5, and that difference can reshape an entire interaction network at an active site or a protein-protein interface. By letting users specify the pH of interest, the server can produce contact maps that reflect the chemistry of a specific biological condition rather than a single default state. The second novelty is support for biological assemblies. Many proteins only do their real work as multimers — symmetric complexes of several identical or complementary chains — and analyzing contacts in the full biological assembly, rather than in a single asymmetric unit extracted from a crystal, can reveal interfaces that would otherwise be missed entirely.

To demonstrate what the platform can do, the authors turned to a pair of proteins that make for a striking natural experiment: Transthyretin, known as TTR, and 5-Hydroxyisourate Hydrolase, or HIUase. The two proteins are evolutionarily and structurally related, sharing a common fold, yet they perform utterly different biological jobs. TTR is a transport protein found in blood and cerebrospinal fluid that carries thyroxine and retinol-binding protein — and, infamously, it is prone to misfolding and aggregation into amyloid fibrils, the hallmark of diseases including familial amyloid polyneuropathy and senile systemic amyloidosis. HIUase, by contrast, is an enzyme involved in purine metabolism in many organisms, catalyzing the hydrolysis of 5-hydroxyisourate as part of the pathway that degrades uric acid; loss of its function is associated with gout, a painful condition caused by urate crystal deposition. Two proteins with such similar architecture but such divergent — and clinically consequential — behaviors are exactly the kind of case where contact-level analysis can expose what the static fold alone cannot.

Running both proteins through COCaDA-web, the researchers found meaningful differences in the patterns of interatomic contacts, particularly in the central cavities of the two proteins. These cavities — the internal spaces that in TTR form the thyroxine-binding channel and in HIUase contribute to the enzyme’s active-site environment — showed distinct contact signatures that help explain how two proteins built on the same structural scaffold came to serve such different functions. The comparison illustrates a broader principle in structural biology: sequence and fold tell only part of the story. The fine-grained geography of atomic interactions, especially within cavities and at interfaces, encodes the functional specialization that evolution has layered onto a shared architectural blueprint. Tools that make those signatures easy to compare, side by side and residue by residue, give researchers a new lens on questions of functional divergence, protein engineering and drug targeting.

The scale of the underlying database deserves emphasis. Three-quarters of a billion contacts, precomputed and indexed, means that much of the drudgery of contact analysis has already been done before a user ever opens the website. A researcher investigating a protein family can pull up precomputed contact data for hundreds of related structures instantly, comparing interaction networks across species, mutants or ligand-bound states without running a single calculation. For proteins not yet in the database, users can submit their own queries and have the server compute contacts on demand, with results delivered in the same dynamic table and 3D visualization environment. The server also integrates with AlphaFold, the deep-learning system that has predicted structures for hundreds of millions of proteins, extending the reach of contact analysis beyond experimentally determined structures into the vast space of computationally predicted ones.

Accessibility is a deliberate design goal. COCaDA-web is freely available at bioinfo.dcc.ufmg.br/cocada-web with no login requirements, and the team has included step-by-step usage guides to lower the barrier for newcomers. That matters because contact analysis has historically been a gatekept skill: the traditional implementations, as the authors note, remain computationally expensive and pose significant scalability and usability challenges. A graduate student in a biology lab without a computing cluster, a clinician curious about the structural basis of an amyloid disease, or a teacher building a lesson on protein structure can all now interrogate the same data that specialists use. The work was funded by Brazilian agencies CAPES, FAPEMIG and CNPq, and the authors acknowledge advice from Carlos Henrique da Silveira, Lucas Bleicher and Miguel Ortega in developing the new features.

The broader significance of tools like COCaDA-web lies in how they reshape the rhythm of discovery in structural bioinformatics. As predicted structures from AlphaFold and experimental structures from cryo-electron microscopy flood the public databases, the bottleneck is shifting from obtaining structures to interpreting them. Contact networks are one of the most information-dense summaries of a structure — a fingerprint that captures chemistry, geometry and environment in a single representation — and making those fingerprints searchable, comparable and visualizable at web speed turns a specialist computation into a routine exploratory act. For diseases of protein misfolding, where the transition from a soluble transporter to a pathological aggregate hinges on subtle shifts in which atoms find which neighbors, that accessibility could accelerate the search for the molecular tipping points. And for the everyday work of characterizing enzymes, engineering binders and annotating newly sequenced genomes, a tool that answers contact questions in under a second may simply become part of how structural questions get asked.

Subject of Research: Interactive web server for exploratory analysis of interatomic contacts in protein structures

Article Title: COCaDA-web: an interactive web server for exploratory analysis of interatomic contacts in proteins

Article References: Lemos, R. P., Mariano, D., Bastos, A. L. A., Silveira, S. D. A., & de Melo-Minardi, R. C. (2026). COCaDA-web: an interactive web server for exploratory analysis of interatomic contacts in proteins. BMC Bioinformatics. https://doi.org/10.1186/s12859-026-06624-8

Image Credits: AI Generated

DOI: 10.1186/s12859-026-06624-8

Keywords: COCaDA-web, protein contacts, structural bioinformatics, Protein Data Bank, web server, interatomic interactions, Transthyretin, amyloidosis, 5-Hydroxyisourate Hydrolase, protein structure, biological assemblies, protonation

The biology behind the disease explains why the new drugs work the way they do. Transthyretin is a transport protein produced almost entirely in the liver, circulating in the blood as a four-part tetramer that carries thyroxine and retinol-binding protein. In ATTR amyloidosis, the tetramer dissociates into individual subunits that misfold and aggregate into insoluble fibrils that deposit in the myocardium. Dissociation of the tetramer is the rate-limiting step of this amyloidogenic cascade, which is precisely where the first drug class intervenes. Tafamidis, approved in Germany in 2020, and acoramidis, approved in 2025, are so-called kinetic stabilizers that selectively bind to the unoccupied thyroid hormone-binding site of the tetramer, locking it shut and preventing the misfolding that leads to amyloid deposition.

The second class attacks the problem upstream. Vutrisiran, a small interfering RNA approved for ATTR-CM in 2025, is a double-stranded RNA molecule conjugated to a sugar that escorts it into liver cells, where it binds the messenger RNA encoding transthyretin and triggers its degradation. The result is a marked, durable reduction in hepatic production of the precursor protein, with a mean maximum TTR reduction of 57 to 97 percent sustained for at least 90 days after each subcutaneous injection. Rather than stabilizing the protein that already exists, vutrisiran essentially shuts down the factory, and clinical outcomes in the phase 3 HELIOS-B trial now document what that pharmacologic logic delivers in patients.

The evidence base for all three drugs rests on landmark randomized trials, each with its own design and population. For tafamidis, the pivotal ATTR-ACT trial randomized 441 patients, predominantly older men with the wild-type form of the disease, to drug or placebo on top of standard heart failure therapy. Over 30 months, tafamidis significantly reduced the hierarchical composite of all-cause mortality and cardiovascular hospitalization, with an absolute mortality reduction of 13.4 percent and a strikingly low number needed to treat of eight. Long-term extension analyses confirmed a sustained survival benefit beyond five years for patients who started tafamidis early, compared to those who began therapy only after the trial ended. That pattern, in which delayed treatment never fully caught up, has become the most consistent lesson across the entire field.

Acoramidis, designed to mimic the super-stabilizing T119M transthyretin variant, produced one of the most compelling results in the ATTRibute-CM trial. In a modified intention-to-treat population of 611 patients followed for 30 months, acoramidis achieved a win ratio of 1.8 on a hierarchical endpoint combining mortality, cardiovascular hospitalizations, NT-proBNP change and six-minute walk distance. Although the mortality effect alone did not reach statistical significance at 30 months, it did so after 42 months in the open-label extension, with a hazard ratio of 0.64. Notably, treatment with acoramidis raised serum TTR levels early, and each 5 milligrams per deciliter increase in TTR was associated with a 31.6 percent reduction in the risk of all-cause mortality, an observation the panel considers an important pharmacodynamic signal for monitoring therapy.

Vutrisiran’s HELIOS-B trial extended the gene-silencing approach to the cardiomyopathy population with equally impressive results. Over approximately 33 months, vutrisiran reduced the composite of all-cause mortality and recurrent cardiovascular events by 25 to 30 percent in relative terms, and cut all-cause mortality by roughly one third at 42 months. Patients on vutrisiran preserved walking distance, experienced attenuated rises in NT-proBNP detectable as early as six months, and maintained quality of life scores that placebo patients lost. The benefits were most pronounced in patients on monotherapy and in those with less advanced disease, reinforcing the same theme: intervene early, because amyloid burden accumulated before treatment may never be fully recovered.

Given the absence of any head-to-head trial between the three agents, the panel’s central conclusion is deliberately cautious: based on current scientific data, tafamidis, acoramidis and vutrisiran are considered similarly effective for most patients with confirmed ATTR-CM. All three demonstrated significant reductions in all-cause mortality and cardiovascular hospitalizations in their respective phase 3 studies, with comparable tolerability profiles. The one clear exception concerns patients with hereditary ATTR-CM and a mixed phenotype, meaning concurrent cardiomyopathy and polyneuropathy, for whom the panel recommends vutrisiran as first-line therapy, based on its demonstrated efficacy against both cardiac and neurological manifestations in the HELIOS-A and HELIOS-B programs.

Safety data, while reassuring for all three agents, differ in the details that matter for individual patients. Tafamidis is generally well tolerated, with mild gastrointestinal symptoms such as diarrhea and constipation as the most frequent complaints, and a permanent discontinuation rate of only 0.8 percent in the pivotal trial. Acoramidis also showed a favorable profile, though mild to moderate gastrointestinal effects including diarrhea, nausea and dyspepsia occurred more frequently than with placebo, and gout was observed more often in treated patients. An early, reversible rise in serum creatinine was noted, but renal pharmacokinetics were not meaningfully affected and no dose adjustment is required. Vutrisiran, administered subcutaneously every three months, showed a safety profile comparable to placebo across age groups, with transient injection-site reactions in about 2 percent of patients, though patients require daily vitamin A supplementation of 2500 international units, typically at their own expense in Germany, because gene silencing also reduces this essential nutrient’s transport protein.

The consensus document goes well beyond pharmacology, addressing the practical realities that determine whether patients actually receive treatment. Annual therapy costs in Germany currently range from approximately 100,000 to 150,000 euros per patient, a figure that fell after a 50 percent price reduction for vutrisiran at the end of 2025 but still raises serious cost-effectiveness concerns, given that the median age at diagnosis is around 80 years. The authors note that prescribing is almost exclusively concentrated in specialized amyloidosis centers, creating bottlenecks that delay diagnosis and treatment and worsen prognosis. To counter this, the panel proposes a shared care model in which centers establish the diagnosis and initiate therapy, while trained office-based physicians handle routine monitoring and ongoing prescriptions. Early initiation, the authors emphasize, matters far more than the specific choice of substance, since open-label extension data consistently show that patients who started therapy late never regained the survival advantage of those treated from the beginning.

For patients in whom therapy is already underway, the consensus defines multimodal criteria for recognizing disease progression, including heart failure hospitalization, diuretic intensification, NT-proBNP increases above 700 picograms per milliliter with a relative rise exceeding 30 percent, eGFR declines greater than 20 percent, worsening quality of life scores, or NYHA class deterioration. Fulfillment of at least two criteria after 12 months of adequate therapy, without another identifiable cause, may prompt consideration of switching substance or class, although the panel acknowledges that prospective data to guide such switches do not yet exist. As a rule of thumb, specific therapy requires two to three years to deliver significant prognostic benefit, meaning patients with a life expectancy under two years are unlikely to benefit and should instead receive optimal supportive care. The panel also cautions against combination therapy, which appears safe but lacks randomized evidence of incremental efficacy, and points to a rich pipeline of future options, including the antisense oligonucleotide eplontersen, the NSAID-derived stabilizer diflunisal, CRISPR-Cas9 gene editing with nexiguran ziclumeran, and amyloid-depleting antibodies such as NI006, which in early trials demonstrated actual removal of cardiac amyloid deposits. For a disease once written off as untreatable, the consensus marks less an endpoint than a beginning.

Subject of Research: Expert consensus recommendations for disease-modifying drug treatment of transthyretin amyloid cardiomyopathy in Germany

Article Title: Specific treatment of ATTR-CM in Germany—expert consensus of the German Society of Amyloid Diseases (DGAK) and German Cardiac Society (DGK)

Article References: aus dem Siepen, F., Trenkwalder, T., Aßmus, B., Kindermann, I., Lavall, D., Spethmann, S., Michel, L., Hansen, T., Kruck, S., Rischpler, C., Knebel, F., Schwarting, S. K., Bavendiek, U., Papathanasiou, M., Hegenbart, U., Yilmaz, A., Hahn, K., Carpinteiro, A., Pfister, R., & Morbach, C. (2026). Specific treatment of ATTR-CM in Germany—expert consensus of the German Society of Amyloid Diseases (DGAK) and German Cardiac Society (DGK). Clinical Research in Cardiology. https://doi.org/10.1007/s00392-026-03006-1

Image Credits: AI Generated

DOI: 10.1007/s00392-026-03006-1

Keywords: ATTR-CM, transthyretin amyloid cardiomyopathy, tafamidis, acoramidis, vutrisiran, amyloidosis, heart failure, TTR stabilizers, gene silencing, DGAK, DGK, expert consensus

Mass spectrometry-based amyloid typing has earned a reputation as the gold standard for identifying the amyloidogenic protein in tissue deposits. By shredding laser-microdissected amyloid plaques into peptides and reading their mass spectra, laboratories can distinguish among more than thirty amyloid types with a specificity that immunohistochemistry and immunofluorescence simply cannot match. Yet the technique has remained confined largely to a handful of reference laboratories because it depends on nanoflow liquid chromatography, in which solvents are pushed through capillaries with inner diameters measured in tens of micrometers. Nanoflow systems deliver exquisite sensitivity, but they come with steep up-front costs, demanding maintenance, long column equilibration times, and a level of operational complexity that deters routine clinical adoption.

The Stanford team, led by Morgan W. Mann and Fangjun Chen with senior authors Megan L. Troxell and Ruben Y. Luo, set out to re-engineer the workflow so that it could run on the high-flow liquid chromatography systems already humming away in hospital laboratories. Their solution rests on two complementary innovations: a sample preparation method called suspension trapping, known commercially as S-Trap, and an acquisition strategy known as data-independent acquisition, or DIA. Together, these techniques allow the analysis of microdissected amyloid plaques using conventional-flow chromatography coupled to tandem mass spectrometry, without sacrificing the diagnostic accuracy that clinicians rely upon.

Suspension trapping is the quieter revolution of the two. In traditional proteomics sample preparation, proteins extracted from tiny tissue fragments must be digested into peptides through a series of solution exchanges, buffer removals, and cleanups that consume time and lose precious material at every step. The S-Trap approach instead traps proteins on a quartz filter matrix as they precipitate out of an acidic methanol-containing buffer. Digestion enzymes then pass through the trap, generating peptides that are eluted in a single, efficient step. The method is fast, robust, and minimizes sample loss, which matters enormously when the starting material consists of a few thousand cells harvested by laser capture microdissection from a formalin-fixed paraffin-embedded tissue section.

Data-independent acquisition addresses the other half of the problem. In classical data-dependent acquisition, the mass spectrometer selects the most intense ions in each scan for fragmentation, a stochastic process that can miss low-abundance peptides and produces data that are tedious to align across runs. DIA, by contrast, fragments all ions within successive wide mass windows, systematically recording fragment spectra for essentially everything in the sample. The resulting data are reconstructed computationally against spectral libraries, yielding consistent and quantitative peptide identifications. Because DIA tolerates the higher flow rates, wider chromatographic peaks, and greater sample loads of high-flow chromatography, it made the leap away from nanoflow feasible rather than merely aspirational.

To translate raw proteomic data into a diagnosis, the researchers also developed a custom selection heuristic that sifts through the hundreds of proteins detected in each plaque and identifies the most likely amyloidogenic culprit. Amyloid deposits are not pure; they sweep up serum proteins, immunoglobulin fragments, and extracellular matrix components as they form. Distinguishing the genuine amyloidogenic protein from innocent bystanders requires weighing total protein abundance, the presence of type-specific signature peptides, and the biological plausibility of each candidate. The heuristic automates this judgment, reducing an expert curation task that could take hours into a reproducible computational step suitable for a busy clinical workflow.

The performance data are striking. Working with laser capture microdissected plaques from 47 patient samples, 10 from cardiac biopsies and 37 from renal biopsies, the team split the material into a training set of 25 samples and an independent testing set of 22. The high-flow LC-DIA-MS/MS method identified the amyloidogenic protein in approximately 96 percent of plaques in both sets, a success rate comparable to established nanoflow approaches. The two inaccuracies observed across the cohort both traced to difficulties in identifying immunoglobulin lambda proteins, once in a specimen obtained after treatment had altered the composition of the deposits and once in a plaque containing two distinct amyloid types simultaneously. These edge cases, the authors note, define the boundaries of the method rather than undermining its general utility.

Reducing the sample preparation workflow to under eight hours carries practical significance beyond convenience. Amyloidosis is increasingly recognized as an urgent diagnosis; cardiac involvement can progress rapidly, and new therapies such as transthyretin stabilizers and silencing agents work best when started early. Every hour shaved from the analytical pipeline shortens the time between biopsy and answer. Equally important, the shift to high-flow chromatography means the method can run on instruments of the kind already deployed for clinical chemistry assays, drug monitoring, and newborn screening in hospital laboratories. That compatibility could transform amyloid typing from a rarefied referral test into an accessible diagnostic performed locally, at lower cost and with faster turnaround.

The study, published in Clinical Proteomics, was conducted on remnant patient specimens under approved institutional review board protocols and funded through the Stanford University Department of Pathology’s Test Development Program, underscoring its explicitly clinical orientation. The authors acknowledge one commercial entanglement: a collaborative research relationship between one investigator and Thermo Fisher Scientific, which provided technical support. While the method will still require validation in other laboratories and across broader panels of amyloid types, the combination of suspension trapping, data-independent acquisition, and high-flow chromatography represents a credible path toward democratizing molecular amyloid typing, offering patients everywhere the prospect of a faster, more precise answer to the question their treatment ultimately depends on.

Subject of Research: A high-flow liquid chromatography-tandem mass spectrometry method for typing amyloidosis in clinical laboratories

Article Title: Suspension trapping and data-independent acquisition enable high-flow liquid chromatography-tandem mass spectrometry-based amyloidosis typing in clinical laboratories

Article References: Mann, M. W., Chen, F., Zhu, C., Lu, C., Liang, B., Kambham, N., Troxell, M. L., & Luo, R. Y. (2026). Suspension trapping and data-independent acquisition enable high-flow liquid chromatography-tandem mass spectrometry-based amyloidosis typing in clinical laboratories. Clinical Proteomics. https://doi.org/10.1186/s12014-026-09628-x

Image Credits: AI Generated

DOI: 10.1186/s12014-026-09628-x

Keywords: amyloidosis, mass spectrometry, proteomics, data-independent acquisition, suspension trapping, liquid chromatography, clinical diagnostics, laser capture microdissection, AL amyloidosis, ATTR amyloidosis, tandem mass spectrometry, clinical proteomics